Coupling biomass chemical looping combustion system

Abstract

The utility model discloses a coupled biomass chemical looping combustion system which comprises an air reactor, a cyclone separator, a return feeder and a fuel reactor, the air reactor is communicated with the return feeder through the cyclone separator, the air reactor is configured to complete an oxidation reaction based on the received oxygen carrier and air, the generated oxidation-state oxygen carrier is conveyed to the cyclone separator under the driving of flue gas, and the corresponding oxidation-state oxygen carrier is conveyed to the return feeder through the cyclone separator; the return feeder is respectively communicated with the air reactor and the fuel reactor through a material conveying pipe, the input oxidation-state oxygen carrier is input into the air reactor and / or the fuel reactor by the return feeder, and the fuel reactor completes an oxidation-reduction reaction based on the received oxidation-state oxygen carrier and biomass fuel; the fuel reactor is used for inputting the reduced oxygen carrier into the air reactor through a return pipe; and the exhaust port of the fuel reactor is provided with a carbon dioxide trapping device so as to complete trapping of discharged carbon dioxide.

Description

Technical Field

[0001] The utility model belongs to the technical field of chemical chain combustion, and in particular relates to a coupled biomass chemical chain combustion system. Background Art

[0002] Chemical looping combustion technology is a new type of flameless combustion technology with extremely high energy efficiency. It only releases CO2 and H20 while efficiently burning fuel. High-purity CO2 can be obtained through simple condensation. It is one of the most promising carbon capture technologies. It can significantly reduce the cost of carbon capture and is of great significance to reducing environmental pollution and greenhouse gas emissions.

[0003] There are a large number of circulating fluidized bed power generation units in the industry. Coal-fired units are one of the most intense sources of carbon emissions and are one of the obstacles to achieving the goals of carbon peak and carbon neutrality.

[0004] Therefore, there is an urgent need for a new combustion system that can convert ordinary combustion into chemical chain combustion. Utility Model Content

[0005] The purpose of the utility model is to overcome the problems of the prior art and disclose a coupled biomass chemical chain combustion system, which converts ordinary combustion into chemical chain combustion, thereby reducing the carbon emission intensity of the existing circulating fluidized bed generator set.

[0006] The purpose of the utility model is achieved through the following technical solutions:

[0007] A coupled biomass chemical chain combustion system, the chemical chain combustion system comprising: an air reactor, a cyclone separator, a material return device and a fuel reactor;

[0008] The air reactor is connected to the return device via a cyclone separator, and the air reactor is configured to complete an oxidation reaction based on the received oxygen carrier and air, and the generated oxidized oxygen carrier is transported to the cyclone separator driven by the flue gas, and the corresponding oxidized oxygen carrier is transported to the return device via the cyclone separator;

[0009] The returner is connected to the air reactor and the fuel reactor respectively through the material conveying pipe, and the input oxidized oxygen carrier is input to the air reactor and / or the fuel reactor by the returner, and the fuel reactor completes the redox reaction based on the received oxidized oxygen carrier and the biomass fuel to generate a mixed flue gas composed of water vapor and CO2 and a reduced oxygen carrier;

[0010] The bottom end of the fuel reactor is provided with a return pipe connected to the air reactor, and the reduced oxygen carrier is input into the air reactor through the return pipe; the exhaust port of the fuel reactor is provided with a carbon dioxide capture device to capture the exhaust carbon dioxide.

[0011] According to a preferred embodiment, the chemical chaining combustion system further comprises a water-cooled screw feeder, and the water-cooled screw feeder is connected to the fuel reactor to complete the input of biomass.

[0012] According to a preferred embodiment, the biomass fuel is mainly agricultural and forestry waste particles.

[0013] According to a preferred embodiment, CO2 and / or water vapor are introduced into the water-cooled screw feeder during the material input process, so that the fuel reactor is in a bubbling operation state.

[0014] According to a preferred embodiment, a conical valve is provided on the material conveying pipe between the return device and the fuel reactor to control the quantity of the oxidized oxygen carrier material input into the fuel reactor.

[0015] According to a preferred embodiment, the air reactor is a circulating fluidized bed boiler.

[0016] According to a preferred embodiment, the cyclone separator is used for gas / solid separation of the oxygen carrier and the high-temperature flue gas of the air reactor, and discharges the high-temperature flue gas.

[0017] According to a preferred embodiment, the fluidization gas and reaction gas for the material inside the air reactor is air, and the corresponding air is provided by an external air supply device.

[0018] According to a preferred embodiment, the oxygen carrier is a metal oxide, including Ni, Fe, Cu, Co, Mn and composite metal oxides thereof.

[0019] The above-mentioned main scheme of the utility model and its further optional schemes can be freely combined to form multiple schemes, all of which are schemes that can be adopted and claimed for protection by the utility model. After understanding the scheme of the utility model, those skilled in the art can understand that there are many combinations based on the existing technology and common knowledge, all of which are technical schemes to be protected by the utility model, and they are not exhaustively listed here.

[0020] Beneficial effects of the utility model:

[0021] In view of the problem of high carbon emission intensity of existing circulating fluidized bed boilers, the utility model transforms them into chemical chain combustion systems by adding an external bubbling bed. During operation, an oxygen carrier circulation is established, the original circulating fluidized bed boiler is used as an air reactor, and the added bubbling bed is used as a fuel reactor. Biomass fuel is put into the fuel reactor for reaction, and the CO2 at its outlet is captured, thereby reducing the carbon emission intensity of the circulating fluidized bed generator set. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is the principle structure diagram of the utility model coupled biomass chemical chain combustion system;

[0023] Among them, 1-air reactor, 2-cyclone separator, 3-returner, 4-conical valve, 5-fuel reactor, 6-return pipe, 7-water-cooled screw feeder. DETAILED DESCRIPTION

[0024] The following describes the implementation of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific implementations, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0025] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0026] In the description of the present utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate the orientation or position relationship based on the orientation or position relationship shown in the accompanying drawings, or the orientation or position relationship in which the utility model product is usually placed when in use, which is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0027] In addition, the terms "horizontal", "vertical", "overhanging" and the like do not mean that the components are required to be absolutely horizontal or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0028] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] In addition, the present utility model should point out that, in the present utility model, if the specific structure, connection relationship, position relationship, power source relationship, etc. are not specifically written out, the structure, connection relationship, position relationship, power source relationship, etc. involved in the present utility model are all known by technical personnel in this field on the basis of existing technology without creative work.

[0030] The utility model discloses a coupled biomass chemical chain combustion system. The chemical chain combustion system comprises: an air reactor 1, a cyclone separator 2, a material return device 3 and a fuel reactor 5.

[0031] The air reactor 1 is connected to the return device 3 via the cyclone separator 2. The air reactor 1 is configured to complete an oxidation reaction based on the received oxygen carrier and air. The generated oxidized oxygen carrier is transported to the cyclone separator 2 driven by the flue gas, and the corresponding oxidized oxygen carrier is transported to the return device 3 via the cyclone separator 2.

[0032] The return device 3 is connected to the air reactor 1 and the fuel reactor 5 respectively through the material conveying pipe, and the input oxidized oxygen carrier is input into the air reactor 1 and / or the fuel reactor 5 by the return device 3, and the fuel reactor 5 completes the redox reaction based on the received oxidized oxygen carrier and biomass fuel to generate a mixed flue gas composed of water vapor and CO2 and a reduced oxygen carrier.

[0033] A return pipe 6 is provided at the bottom of the fuel reactor 5 to communicate with the air reactor 1, and the reduced oxygen carrier is input into the air reactor 1 through the return pipe 6; a carbon dioxide capture device is provided at the exhaust port of the fuel reactor 5 to capture the discharged carbon dioxide.

[0034] Preferably, the chemical chain combustion system further comprises a water-cooled screw feeder 7, which is connected to the fuel reactor 5 to complete the input of biomass. The feeding height is 0.5 to 2.0 m from the air distribution plate. Furthermore, the biomass fuel is mainly agricultural and forestry waste particles.

[0035] Preferably, CO2 and / or water vapor are introduced into the water-cooled screw feeder 7 during the material input process, so that the fuel reactor 5 is in a bubbling operation state.

[0036] Preferably, a conical valve 4 is provided on the material conveying pipe between the return device 3 and the fuel reactor 5 to control the quantity of the oxidized oxygen carrier material input into the fuel reactor 5 .

[0037] Preferably, the air reactor 1 is a circulating fluidized bed boiler.

[0038] Preferably, the cyclone separator 2 is used for gas / solid separation of the oxygen carrier and the high-temperature flue gas of the air reactor 1, and discharges the high-temperature flue gas.

[0039] Preferably, the fluidization gas and reaction gas for the materials inside the air reactor 1 are air, and the corresponding air is provided by an external air supply device.

[0040] Preferably, the oxygen carrier is a metal oxide, including Ni, Fe, Cu, Co, Mn and composite metal oxides thereof.

[0041] refer to Figure 1 As shown in the figure, the arrows indicate the flow direction of the oxygen carrier. The oxygen carrier circulation process is:

[0042] When the device is running, CO2 or water vapor is introduced into the fuel reactor 5 for bubbling operation, and the biomass fuel is fed into the fuel reactor 5 through the water-cooled screw feeder 7. The introduction ratio of CO2 and water vapor can be adjusted according to the effect of the gasification reaction. The oxygen carrier and the biomass react in the fuel reactor. After the oxygen carrier is reduced, it enters the air reactor 1 through the return pipe 6 for oxidation. The outlet of the fuel reactor 5 is high-concentration CO2.

[0043] The air reactor 1 is a conventional circulating fluidized bed boiler, which is operated by passing air to oxidize the oxygen carrier flowing in from the fuel reactor 5. After the oxygen carrier is separated by the cyclone separator 2, a part of it is directly returned to the air reactor 1 through the return device 3, and the other part flows into the fuel reactor 5 through the return device 3. The amount of solids entering the fuel reactor 5 is controlled by the opening of the conical valve 4, which is used to control the material level height of the oxygen carrier in the fuel reactor 5, thereby completing the solid circulation process.

[0044] Compared with the general circulating fluidized bed boiler, the boiler is modified by adding an external bubbling bed as the fuel reactor 5, converting it into a chemical chain combustion device, adding biomass fuel into the fuel reactor 5 for reaction, and capturing the CO2 at its outlet to solve the problem of high carbon emission intensity of the circulating fluidized bed power generation unit.

[0045] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A coupled biomass chemical chain combustion system, characterized in that: The chemical looping combustion system comprises: an air reactor (1), a cyclone separator (2), a material return device (3) and a fuel reactor (5); The air reactor (1) is connected to the return device (3) via the cyclone separator (2). The air reactor (1) is configured to complete an oxidation reaction based on the received oxygen carrier and air, and the generated oxidized oxygen carrier is transported to the cyclone separator (2) driven by the flue gas, and the corresponding oxidized oxygen carrier is transported to the return device (3) via the cyclone separator (2); The return device (3) is connected to the air reactor (1) and the fuel reactor (5) respectively through the material conveying pipe, and the input oxidized oxygen carrier is input into the air reactor (1) and / or the fuel reactor (5) by the return device (3), and the fuel reactor (5) completes the redox reaction based on the received oxidized oxygen carrier and the biomass fuel to generate a mixed flue gas composed of water vapor and CO2 and a reduced oxygen carrier; The bottom end of the fuel reactor (5) is provided with a return pipe (6) which is connected to the air reactor (1), and the reduced oxygen carrier is input into the air reactor (1) through the return pipe (6); the exhaust port of the fuel reactor (5) is provided with a carbon dioxide capture device to capture the discharged carbon dioxide.

2. The chemical looping combustion system according to claim 1, characterized in that: The chemical looping combustion system further comprises a water-cooled screw feeder (7), The water-cooled screw feeder (7) is connected to the fuel reactor (5) to complete the input of biomass fuel.

3. The chemical looping combustion system according to claim 2, characterized in that: The biomass fuel includes agricultural and forestry waste particles.

4. The chemical looping combustion system according to claim 2, characterized in that: The water-cooled screw feeder (7) is accompanied by the introduction of CO2 and / or water vapor during the material input process, so that the fuel reactor (5) is in a bubbling operation state.

5. The chemical looping combustion system according to claim 1, characterized in that: A conical valve (4) is provided on the material conveying pipe between the return device (3) and the fuel reactor (5) to control the quantity of the oxidized oxygen carrier material input into the fuel reactor (5).

6. The chemical looping combustion system according to claim 1, characterized in that: The air reactor (1) is a circulating fluidized bed boiler.

7. The chemical looping combustion system according to claim 6, characterized in that: The fluidization and reaction gas for the materials inside the air reactor (1) is air, and the corresponding air is provided by an external air supply device.

8. The chemical looping combustion system according to claim 1, characterized in that: The cyclone separator (2) is used for gas / solid separation of the oxygen carrier and the high-temperature flue gas of the air reactor (1), and for discharging the high-temperature flue gas.

Images